19. what communication flow is used during a one-on-one conversation?
a. synchronous
b. asynchronous
c. vertical
d. written
20. why is vertical communication important within a business?
a. it allows communication to flow up and down through all levels.
b. it only allows for communication with one person at a time
c. it only allows communication among peers.
d. it only allows upwards communication.
21. what type of communication flow is a company bulletin?
a. asynchronous
b. horizontal
c. s ynchronous
d. one-on-one

19 A) Synchronous.

20 A) It allows communication to flow up and down through all levels.

21 B) Horizontal

Explanation:

19) Synchronous messaging allows the client to that waits for responding from server. it is the two way communication process in which receiver have to respond in a same time. We can say that synchronous is the best method for one-to-one communication.

20) Vertical communication is essential for any firm because it helps the information flow from top to bottom. The flow of information determines the success of an organization that how each of the employee is aligned.  

21) Horizontal communication can be considered as company bulletin. It includes the flow of environment in the same hierarchical level. Like the information regarding to the procurement, must know by each of the employee in the supply chain department. It determines the quality of networking of the employee working in the same environment.